Sheet metal bending machine



July 6, 1965 c. 1. PELTON ETAL SHEET METAL BENDING- MACHINE 4 Sheets-Sheet 1 Filed May 23, 1962 FIG. I

INVENTORS CLYDE l. PELTON BY EDWARD RSCHNEIDER ATTO EY July 6, 1965 c. I. PELTON ETAL SHEET METAL BENDING MACHINE mum INVENTORS CLYDE I. PELTGI EDWARD P. SCHNEIDER 4 Sheets-Sheet 2 ATTOR Filed May 23. 1962 July 6, 1965 c. PELTON ETAL SHEET METAL BENDING MACHINE Filed May 23, 1962 5 aw m w fiQMHM UH HMM H u. m v I w .w 4 w L mw 1 V H MMJL mv T CLYM l. PE L EDWARD P. SCHNEIDER TORIEY y 5 c. l. PELTON ETAL 3,192,759

SHEET METAL BENDING MACHINE Filed May 23, 1962 4 Sheets-Sheet 4 ENTO cum: I. FKIIIIIXTON Rs EDWARDR scHNemsR United States Patent 3,192,759 SHEET METAL BENDING MACHINE Clyde 1. Peiton and Edward P. Schneider, Warren, Ohio, assignors to The Taylor-Winfield Corporation, Warren, Ohio, a corporation of Ohio Filed May 23, 1962, Ser. No. 196,978 7 Claims. (Cl. 72-319) This invention relates to sheet metal bending equipment and more particularly to apparatus for converting flat and flanged sheet metal stock into cabinets and other articles having both outside and inside or reverse corners formed by bending the stock around anvil dies. It has heretofore been proposed, in making rectangular cabinet structures, for example, to bend or wrap a relatively fiat sheet of metal over a rectangular cantilevered anvil die by means of one or a plurality of swingable bending wings which slideably mount the bending dies. In some applications, particularly if the product is to have a closed side wall section, a secondary bending wing is pivotally mounted on the outer free end of a pair of main or primary bending wings so that the stock may be bent around all the four corners of a rectangularly-shaped anvil die. This is shown in US. Patent No. 2,557,346. Of course, the stock may be flanged as shown in this patent.

In all the above prior apparatus, however, only outside corners may be formed so that if inward indentations of corners are required in the finished product it has heretofore been necessary to form the same in sep arate ancillary equipment. The necessary extra handling and operations involved materially increases the cost of manufacture.

It is accordingly the primary object of the present invention to provide a sheet metal bending machine of the fixed anvil die and pivoted bending wing type which is operative to impart both outwardly and inwardly di-.

rected corners and/ or indentations to a sheet metal blank while the blank remains in the same machine and is continuously clamped by its initial clamping means. This desirable result in obtained, in accordance with the principles of our invention, by pivotally mounting a pair or more of ancillary bending wings on the primary or main bending wing of the bender. One of such ancillary wings may be used to form an inwardly directed corner or indentation either co-extensive with the final outside corner formed by the other or second ancillary wing or oifset from the so formed final outside corner as in the specific embodiment of the invention to be hereinafter described. Alternatively, of course, the ancillary wings may be employed to form two outside corners which have difierent spacings from the first formed corner. Thus, another object of the invention is to provide a wingtype of bending machine which is more versatile as regards the shapes of products which may be formed in one cycle of operation of the apparatus.

The apparatus specifically disclosed herein for illus trative purposes is designed to form a rectangular sheet metal enclosure in which a portion of one of the four corners is bent inwardly to form an outwardly opening recess. This provides, along one of the edges of the product, both an outwardly directed and an inwardly directed corner, and to accomplish the same the initial flat workpiece must, of course, be slit longitudinally from one of the end edges of the blank.

The above and other specific objects and advantages of the invention will become apparent upon consideration of the following specification and accompanying drawing where there is disclosed the above mentioned representative embodiment of the invention.

In the drawing:

FIGURE 1 is an end view of an assembled bending Patented July 6, 1965 machine constructed in accordance with the principles of our invention;

FIGURE 2 is a partial front elevation of the machine of FIGURE 1;

FIGURE 3 is a fragmentary plan view of a multiple section bending wing of the apparatus of FIGURES 1 and 2;

FIGURES 4 and 5 are detailed views of a portion of the apparatus of FIGURES 1 and 2; and

FIGURES 6 and 7 are side elevations of the multiple section bending wing of the apparatus of FIGURES 1 and 2, showing the wing in open and closed positions, respectively.

In the drawing, reference numeral 10 designates as elongated base on one end of which is rigidly mounted an upstanding frame assembly 11 which supports an anvil die 12, the multiple section bending wing 13 and a welding assembly 14. On the opposite end of the base 10 there is slideably mounted a second frame assembly 15 which mounts a second anvil die 16 and a second bending wing 17. As indicated in FIGURE 2 the assembly comprised of the components 15-17 is movable toward and away from the assembly comprised of the components 11-13 to adjust for different length of products, and interconnecting these assemblies is a belttype of conveyor 18 which is entrained over a pulley 19 driven by shaft 20 (FIG. 1). Inasmuch as the bending wing 17 and its associated anvil die 16 are generally similar in function to corresponding apparatus of the prior art patent referred to above the same will not be further described herein except to state that the flat blank which is brought into the machine by conveying means, not shown, (positioned ahead of the wing 17) and by the conveyor belt 18 is formed and bent at one end by the wing 17 and simultaneously at the other end by the wing 13.

As indicated in FIGURES 1 and 2 and shown more clearly in FIGURE 7, the anvil die 12 has a recess 21 in one of its corners into which the tab of the flat sheetlike blank is to be bent to form the inside corner of the product. This bending as well as the bending of the remaining portion of the right end section of the blank to form the outer corner of the product is accomplished by the wing assembly 13 which will now be described.

The wing assembly 13 is mounted on an inverted U- shaped carried 22 which is guided for vertical sliding movement on gibs 23 which are rigidly carried by upstanding members of the frame assembly 11. A cylinder 24 is provided to raise and lower this carrier 22 and to exert a clamping pressure on the workpiece to hold the same tight up against the underside of the anvil die comprised of the spaced arms 27 which are rigidly interconnected by a heavy strut 28. Slideably mounted on this wing in ways 29 is a die carrier 30 having outwardly extending side arm 31. By means of an eccentric pin connection, not particularly shown herein, on the I pivotal axis 26, the die carrier 30 is caused to slide backwards a slight mount as the wing comprised of parts 27, 28 swing upwardly, all as fully explained in US. Patent No. 2,937,686.

The wing comprised of the parts 27 and 28 is arranged to be swung upwardly by a pair of cylinders 32 which are pivotally mounted on side sections of the vertical slide 22 and which have their rod ends pivotally connected to the wing. In FIGURE 7 the die which is mounted on carrier 36 is shown schematically at 33, and it should be apparent that upon energization of the cylinders 32 this die will bend the flat metal sheet which is clamped to the bottom of the die 12 by the platen upwardly about the radius of the adjacent corner of the die 12.

Pivotally connected to the arms 31 intermediate their ends for swinging movement about an axis 34 is a first sub-wing 35 having a spaced pair of gibs 36 in which is Slideably mounted a second and smaller die carrier 37. This carrier 37 mounts a die 38 (FIG. 7) which upon swinging movement is operative to bend the above mentioned tab of the workpiece about the radius 39 of the die 12 and about the .radiusof the inside corner 49 thereof whereby the upper free end of the tab will project above the top surface of the die 12 as indicated at 41. In other Words, the swinging die 38 in effect bends and wipes the sheet metal of the tab into the recess 21 of the die 12 to form the inside corner of the product as explained above.

In accordance with the theory fully explained in US. Patent No. 2,287,933, the die 38 is caused to have a slight backwards movement with respect to the sub-wing 35 as the latter is swung about the pivot 34 so that the die will merely roll on the sheet metal as the same is being bent about the radius 39 and will not slide on the sheet metal. This is accomplished by journalling a shaft in the sub-wing 35 which mounts a spaced pair of pinions 42 meshing with rack teeth 43 secured to the bottom side of the die carrier 37. Keyed to this shaft is a gear segment 44 which meshes with a fixed pinion 45 mounted on an axis 34. By referring to FIGURE 6 it will be obvious that as the sub-wing 35 swings in a counterclockwise direction the gear segment 44 will be rotated to the left with respect to the sub-wing 35 and thus effect sliding movement of the die carrier 37.

To swing the sub-wing 35 about the axis 34 we provide a cylinder which is pivotally connected adjacent its rod end as at 46 to a bracket, not shown, connected to the first die carrier 33 and which has the free end of its piston rod pivotally connected to the structure of the sub-wing 35.

To bend the remaining portion of the end section of the stock piece about the radius of the upper corner 47 of the die 12 we provide a second sub-wing 48 which is pivotally mounted on the outer ends of the arms 31 for swinging movement about an axis 49. Slideably mounted on this second sub-wing 48 is a third die carrier 50 mounting a bending die 51. Although not particularly shown herein the eccentric pin construction of the above mentioned US. Patent No. 2,937,686 is, in practice, utilized to slightly shift the die 51 with respect to the sub-wing 48 as the die moves about the radius 47 to efiect the rolling action on the stock as described above. To swing the sub-wing 48 about its pivot 49 we provide a cylinder 52 which is pivotally mounted adjacent its rod end to a bracket 53 depending from a strut 54 interconnecting the ends of the arms 31 and'which has the free, end of its rod pivotally connected to the sub-wing 48 as shown at 55. V

The tail end of the stock piece which is bent up and over the die 16 by the component bending wing 17 is previously formed with a small lip and the spacing of the dies 12 and 16 in relation to the total length of the stock piece is such that after the product is formed this lip on the tail end of the stock piece lies against the upwardly protruding end of the tab at the leading end of the stock piece, all as indicated in FIGURE 7. The head end of the workpiece outside the tab is likewise previously lipped and after completion of the bending operations this latter lip lies against a portion of the lip on the tail end of the workpiece. To weld these lips and the protruding end of the tab together weprovide a resistance welding fixture in the form of a pivoted arm 56 mounting welding transformers 57 and tong-type of electrodes 53 (FIG. 2) which are so adjusted and mounted that when the arm 56 is swung downwardly by cylinder 59 at completion of the bending cycle the tong electrodes may be closed onto each other clamping the stock of the lips and protrusion to resistance weld the same together.

In the use of the apparatus described above, the frame assembly 15 is, of course, properly located longitudinally on the base 10 and locked in place so that a predetermined proper spacing will be effected between the anvil dies 16 and 12. With both of the bending assemblies 17 and 13 retracted to lower position an elongated sheet metal workpiece may now be fed into the apparatus on the conveyor 18. When the workpiece is properly located by suitable stops, not shown, both of the bending assemblies 17 and 13 are moved upwardly to clamp the workpiece onto bottom surfaces of the dies 16 and 12, the cylinder 24 moving the bending assembly 13 upwardly and a platen 25 clamping the workpiece to the bottom of the die 12. The wings of the assembly 17 may now be actuated in sequence by the cylinders shown to bend the stock about the lower left and upper left corners of the die 16 to a position wherein this end of the workpiece overlies a portion of the top surface of the die 12 as indicated in FIGURE 7.

As to the operation of the assembly 13, the cylinders 32 are first actuated to bend the workpiece about the lower right corner of die 12, and thereafter the wings carrying the bending dies 38 and 51 (FIGURE 7) may be actuated eithersimultaneously or in sequence by, respectively, the cylinder which is pivoted at 46 and the cylinder 52. The die 38 bends one of the tabs formed by the longitudinal slit in the workpiece about the radiused corner 39 of the die 12 and, in effect, wipes the material of the tab into the recess 21 of the die 12 to form the inside corner 40. The length of the tab is such that after the bonds are made the extreme end of the tab comes up flush with the top of the lip 41 (FIGURE 7) where these parts may be spot welded together by the welder 14.

The die 51 bends the stock of the workpiece which is on the opposite side of the slit from the tab which enters recess 21 about the radiused corner 47 and, again, the length of this section of the workpiece may be such so that its lip edge may lie against the lip 41 for the purpose of being welded together. During the bending process the welder 14 is retracted, and all the parts are so designed that the work may be kept clamped about the dies 12 and 16 by the dies on the assemblies 13 and 17 during the welding operation. Upon completion of the latter all the wings of the assemblies 13 and 17 are retracted, these assemblies are lowered, and the workpiece may be removed from the dies 12 and 16. It is well known in the art that these dies may be collapsed to facilitate removal of the welded product.

It should now be apparent that we have provided novel sheet metal bending equipment which accomplishes the objects initially set out above in that a wider variety of cabinet structures and other products may be quickly and efiiciently formed in a single machine and with the workpiece being positioned and located only once and being initially clamped but once. Of course, the principles of the invention may be employed for a wide variety of other products including, for example, forms in which no inside corner as at 40 (FIGURE 7) is formed but in which a plurality of outside corners as at 39 and 47 (FIGURE7) are variably spaced from the first bent corner (lower right of FIGURE 7). Also, while not particularly shown herein, it should be apparent that the apparatus of the invention may be used to bend flanged stock as in the above mentioned US. Patent No. 2,287,933. Further, various mechanical and design changes from the specific aparatus illustrated may be made within the purview of our invention to accomplish the novel results herein disclosed and contemplated. Reference should therefore be had to the appended claims in determining the scope of the invention.

We claim:

1. A sheet metal bending machine for forming cabinet structures and the like comprising an anvil die having a first linear lower radiused corner about which sheet metal is to be bent, a wing assembly mounted for rotation about the linear axis of said radiused corner and mounting a bending die which engages the sheet metal to wrap the same around said corner to thereby form an end wall of the product, said anvil die having a second radiused corner spaced from the first corner and extending linearly in parallel relation with said first corner, a recess in said anvil die extending inwardly from the linear axis or" said second corner and thus providing a third linearly extending corner in parallel relation with the first and second corners, a pair of separate ancillary bending wings pivotally mounted on said wing assembly for rotation about spaced parallel axes, said ancillary bending wings carrying bending dies to engage the sheet metal and wrap the same closely about said second and third corners, and means carried by said wing assembly to rotate said ancillary bending wings about their respective axes and relative to said wing assembly.

2. Apparatus according to claim 1 further characterized in that said recess is formed with a radiused inside corner spaced inwardly from said third corner, and the bending die which is carried by one of said ancillary wings and which Wraps the sheet metal about said third corner being radiused at its outer free end and having a radial length of such dimension that it wipes the sheet metal into and against said inside corner of the anvil die to thereby form an inside corner on the product.

3. Apparatus according to claim 2 further including a second wing assembly to bend the sheet metal about an opposite side of said anvil die to thereby position an end edge of the sheet metal in substantial registry with a second linearly extending corner of said recess, the arrangement being such that the free end of the sheet metal section which is wiped into said recess may be brought into contact with said end edge of the sheet metal.

4. In a sheet metal bending machine for forming cabinet structures and the like and having a fixed anvil die about which the sheet metal is to be bent, a bending wing assembly having a pair of arms pivotally mounted for movement about a first axis, a first bending die assembly interconnecting said arms and adapted to make a first bend in the sheet metal about said anvil die, a second bending die assembly pivotally mounted on said first die assembly for movement about a second axis parallel to and spaced from said first axis, a third bending die assembly pivotally mounted on said first die assembly for movement about a third axis spaced from and parallel to said first and second axis, power means to swing said arms and said first bending die assembly, and additional power means carried by said first die assembly to swing said second and third bending die assemblies about their respective axes.

5. Apparatus according to claim 4 further characterized in that said first bending die assembly includes means slideably mounting the same on said arms for movement toward and away from said first axis whereby the first bending die may have rolling action on a metal sheet which is being bent around a radius corner on said anvil die, and said second die assembly further including means slideably mounting the same on said first die assembly whereby the second bending die may have rolling action on another portion of the sheet metal as the same is being bent about a second radiused corner on said anvil die which is spaced from the first mentioned radiused corner.

6. A sheet metal bending machine for forming cabinet strutcures and the like comprising a block-like anvil die having a first linearly extending and radiused corner about which a first outside corner may be formed in the product, said anvil die having a second radiused corner spaced from said first corner and parallel thereto and about which a second outside corner may be formed in the product, said anvil die also having a recess extending inwardly from said second corner and terminating in a linearly extending radiused pocket which is parallel with the said first and second corners, a die carrier swingably mounted on the axis of the radius of said first corner and mounting a first die structure for wiping the stock about said first corner, said first die structure swingably mounting a carrier adapted to have swinging movement about the axis of the radius of said second corner, and a second die carried by said second mentioned carrier for wiping the sheet metal stock about said second corner and into said radiused pocket.

7. Apparatus according to claim 6 further including a slip connection between said second die and said second mentioned carrier whereby said second die will have rolling action about the radius of said second corner rather than sliding action, and said slip connection having means to maintain a predetermined parallelism between said second die and the axes of said first and second corners at all times.

References Cited by the Examiner UNITED STATES PATENTS 536,450 3/95 Adams 153-l8 1,694,512 12/28 MacChesney et al. 2l980 X 2,287,933 6/42 Green 153--3 2,845,981 8/58 Green 153-17 2,937,686 5/60 Green 153-46 CHARLES W. LANHAM, Primary Examiner.

RICHARD M. WOOD, Examiner. 

1. A SHEET METEL BENDING MACHINE FOR FORMING CABINET STRUCTURES AND THE LIKE COMPRISING AN ANVIL DIE HAVING A FIRST LINEAR LOWER RADIUSED CORNER ABOUT WHICH SHEET METAL IS TO BE BENT, A WING ASSEMBLY MOUNTED FOR ROTATION ABOUT THE LINEAR AXIS OF SAID RADIUSED CORNER AND MOUTING A BENDING DIE WHICH ENGAGES THE SHEET METAL TO WRAP THE SAME AROUND SAD CORNER TO THEREBY FORM AN END DWALL OF THE PRODUCT, SAID ANVIL DIE HAVING A SECOND RADIUSED CORNER SPACED FROM THE FIRST CORNER AND EXTENDING LINEARLY IN PARALLEL RELATION WITH SAID FIRST CORNER, A RECESS IN SAID ANVIL DIE EXTENDING INARDLY FROM THE LINEAR AXIS OF SAID SECOND CORNER AND THUS PROVIDING A THIRD LINEARLY EXTENDING CORNER IN PARREL RELATION WITH THE FIRST AND SECOND CORNERS, A PAIR OF SEPARATE ANCILLIARY BENDING WINGS PIVOTALLY MOUNTED ON SAID WING ASSEMBLY FOR ROTATION ABOUT SPACED PARALLEL AXES, SAID ANCILLARY BENDING WINGS CARRYING BENDING DIES TO ENGAGE THE SHEET METAL AND WRAP THE SAME CLOSELY ABOUT SAID SECOND AND THIRD CORNERS, AND MEANS CARRIED BY SAID WING ASSEMBLY TO ROTATE SAID ANCILLARY BENDING WINGS ABOUT THEIR RESPECTIVE AXES AND RELATIVE TO SAID WING ASSENBLY. 